MAKE THE GANACHE.,______,In a large bowl, combine 3 pounds chopped semisweet or bittersweet chocolate, 1 1/2 sticks chopped unsalted butter and a pinch of salt.,Pour the hot cream on top.,Let stand for 5 minutes.,Whisk until smooth.,FLAVOR THE GANACHE.,Divide the ganache into 4 bowls.,For each quarter batch, stir in either 1 1/2 tablespoons dark rum, 4 teaspoons pure peppermint oil and 1 teaspoon ground cardamom or 2 teaspoons instant espresso dissolved in 2 teaspoons water.,Cover and refrigerate until firm, 3 hours.,ROLL THE TRUFFLES.,Using a small scoop, drop tablespoons of the ganache onto parchment-lined baking sheets.,Refrigerate for 1 hour.,Using cold, wet hands, roll the ganache into balls.,Coat the truffles in crushed mint candies, chopped almonds, toasted coconut flakes or cocoa powder.